package com.steellee.leeexcel.util;

import com.alibaba.excel.enums.CellDataTypeEnum;
import com.alibaba.excel.metadata.Head;
import com.alibaba.excel.metadata.data.CellData;
import com.alibaba.excel.metadata.data.WriteCellData;
import com.alibaba.excel.write.metadata.holder.WriteSheetHolder;
import com.alibaba.excel.write.style.column.AbstractColumnWidthStyleStrategy;
import lombok.Data;
import org.apache.poi.ss.usermodel.Cell;
import org.springframework.util.ObjectUtils;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author steellee
 * @date 2023-3-1
 * 设置自适应列宽
 */
@Data
public class CustomCellWriteHandler extends AbstractColumnWidthStyleStrategy {
    private Integer columnWidth;
    private Map<Integer, Map<Integer, Integer>> CACHE = new HashMap<>();

    @Override
    protected void setColumnWidth(WriteSheetHolder writeSheetHolder, List<WriteCellData<?>> cellDataList
            , Cell cell, Head head, Integer integer, Boolean isHead) {
        boolean needSetWidth = isHead || !ObjectUtils.isEmpty(cellDataList);
        if (needSetWidth) {
            if (null != columnWidth) {
                writeSheetHolder.getSheet().setColumnWidth(cell.getColumnIndex(), columnWidth * 256);
            } else {
                Map<Integer, Integer> maxColumnWidthMap = CACHE.get(writeSheetHolder.getSheetNo());
                if (maxColumnWidthMap == null) {
                    maxColumnWidthMap = new HashMap<>();
                    CACHE.put(writeSheetHolder.getSheetNo(), maxColumnWidthMap);
                }
                Integer useColumnWidth = this.dataLength(cellDataList, cell, isHead);
                if (useColumnWidth>= 0) {
                    if (useColumnWidth> 30) {
                        useColumnWidth = 30;
                    }
                    Integer maxColumnWidth = maxColumnWidthMap.get(cell.getColumnIndex());
                    if (null == maxColumnWidth) {
                        maxColumnWidth = 0;
                    }
                    if (useColumnWidth * 256> writeSheetHolder.getSheet().getColumnWidth(cell.getColumnIndex())
                            && useColumnWidth> maxColumnWidth) {
                        maxColumnWidthMap.put(cell.getColumnIndex(), useColumnWidth);
                        writeSheetHolder.getSheet().setColumnWidth(cell.getColumnIndex(), useColumnWidth * 256);
                    }
                }
            }
        }
    }

    private Integer dataLength(List<WriteCellData<?>> cellDataList, Cell cell, Boolean isHead) {
        if (isHead) {
            return cell.getStringCellValue().getBytes().length;
        } else {
            CellData cellData = cellDataList.get(0);
            CellDataTypeEnum type = cellData.getType();
            if (type == null) {
                return -1;
            } else {
                switch (type) {
                    case STRING:
                        return cellData.getStringValue().getBytes().length;
                    case BOOLEAN:
                        return cellData.getBooleanValue().toString().getBytes().length;
                    case NUMBER:
                        return cellData.getNumberValue().toString().getBytes().length;
                    default:
                        return -1;
                }
            }
        }
    }
}